I think normally the G sensor can trigger when you slam the door, but if there is a buffer you probably see you opening the door as the very first in that event file.
Your only option as i understand it is to lover the sensitivity for the G sensor, or disable it all together, if that dont affect the parking mode.
Ideally you want two G sensor trigger value sets, one for using while driving, and the other more sensitive set for use while parked, this way you can disable the driving G sensor values as i am sure you will feel if you have a crash or ding when driving.